An important consideration in building envelope design and construction is the air and water barrier(s) located behind the exterior facade of the building, as well as the connection of the façade over the air and water barrier(s). Traditional building envelope design (and modifications thereof) requires multi-pass installation, in which multiple separate components are sequentially installed on top of one another to achieve the thermal and moisture protection for the building interior. This typically requires a separate trade group to apply/attach each component, adding to the complication, cost, reliability and overall time needed to construct a building. Additionally, attachment of the exterior façade to the air and water barrier(s) compromises the barrier.
FIG. 1 shows a traditional, multi-component wall construction. As shown in FIG. 1, a barrier panel element 20 is attached to the outer surface of the framing studs 10 and batt insulation 15 is located in the stud cavity. A building wrap 30 is applied (typically sprayed) about the barrier panel element 20, and then the exterior façade 40 is attached by extending an anchor (such as a screw, nail, support bracket, etc.) through the wrap 30 and barrier panel element 20 and into the studs 10. This is referred to as a “triple-pass” system, in which a first trade group typically applies/installs the barrier panel element (pass 1), a second trade group applies the wrap (pass 2), and a third trade group installs the façade (pass 3). Because the exterior façade anchor extends through the wrap and barrier panel element, the air, water, vapor and thermal barrier(s) of this design is compromised. This creates an increased concern when an anchor for the exterior façade inadvertently misses a stud when it is installed in pass 3, as a hole is created in the barrier(s) that is not filled (at least in part) by the anchor (as is the case when an anchor extends into the stud).
Adoption of new building codes (such as ASHRAE 90.1-2007) has required increased energy performance requirements for building envelopes, which are not met by the traditional multi-component wall construction shown in FIG. 1. As a result, several alternative modifications of the traditional construction have been proposed and utilized to meet the newer code requirements. A first such alternative is shown in FIG. 2. As shown in FIG. 2, a barrier panel element 20 is attached to the outer surface of the framing studs 10. A building wrap 30 is applied about the barrier panel element 20, and then an insulation panel 15 is applied over the building wrap 30. Finally, the exterior façade 40 is attached by extending an anchor (such as a screw, nail, support bracket 50, etc.) through the insulation panel 15, wrap 30 and barrier panel element 20 and into the studs 10. This also is referred to as a “triple-pass” system, in which a first trade group typically applies/installs the barrier panel element (pass 1), a second trade group applies the wrap (pass 2), and a third trade group installs the insulation panel and façade (pass 3). Because the exterior façade anchor extends through the insulation panel, wrap and barrier panel element, the air, water, vapor and thermal barrier(s) of this design is still compromised. This too creates an increased concern when an anchor for the exterior façade inadvertently misses a stud when it is installed in pass 3, as a hole is created in the barrier(s) that is not filled (at least in part) by the anchor (as is the case when an anchor extends into the stud).
A second alternative to the traditional multi-component wall construction design that has been proposed to meet new code requirements is shown in FIG. 3. As shown in FIG. 3, a barrier (may include insulation functionality as well) panel element 20 is attached to the outer surface of the framing studs 10, and a spray insulation 15 is applied in the stud cavity. A building wrap 30 is applied about the barrier panel element 20, and then the exterior façade 40 is attached by extending an anchor (such as a screw, nail, support bracket, etc.) through wrap 30 and barrier panel element 20 and into the studs 10. This also is referred to as a “triple-pass” system, in which a first trade group typically applies/installs the barrier panel element (pass 1), a second trade group applies the wrap (pass 2), and a third trade group installs the façade (pass 3). Because the exterior façade anchor extends through the wrap and barrier panel element, the air, water, vapor and thermal barrier(s) of this design also is compromised. This again creates an increased concern when an anchor for the exterior façade inadvertently misses a stud when it is installed in pass 3, as a hole is created in the barrier(s) that is not filled (at least in part) by the anchor (as is the case when an anchor extends into the stud).
In an attempt to overcome one or more of the problems identified with respect to the multi-pass designs of the prior art, several “single pass” systems have been developed. Examples of such systems are shown and described in U.S. Pat. No. 7,748,181 (the '181 Patent), and in Exhibits B, C and D to U.S. provisional application No. 61/509,109 filed on Jul. 19, 2011, which depict the Invelope/Metalwrap systems by Centria, the entire disclosures of which are incorporated herein by reference. Referring to FIGS. 7 and 9 of the '181 Patent, a first single pass system includes barrier panels 106a and 106b that are interconnected together via tongue and groove type connections. The barrier panels are attached to the framing of the building and provide air, water, vapor and thermal barrier(s) for the building structure, as well as structural support for an exterior façade system. As is shown in FIG. 7, barrier panel 106b is attached to the stud using clip 144 and screw 146. Clip 144 includes downturned central flange portion 148 which penetrates into a foam portion of the top of panel 106b. The screw 146 extends through the main body portion 150 of clip 144, through panel 106b and into the stud. The lower end of panel 106a is held into position via the tongue and groove connection with panel 106b, and the upper end of 106a is attached to the stud using a clip and screw in the same manner described with respect to panel 106b. As is shown in FIG. 9 of the '181 Patent, a z-shaped subframe 160 is attached to the panels 106 (preferably at their horizontal joint 124) by extending screw 162 through multiple layers of steel 164-168 of the panels 106. The exterior façade panels are then attached to the z-shaped subframe via screws 172. This system is considered a single pass system in that the barrier panels and façade are typically installed by a single trade group. While this system overcomes many of the problems associated with multi-pass designs, the attachment of the subframe to support the façade panels directly to the barrier panels limits the structural support available for the façade, and also potentially exposes the foam core of the barrier panels to moisture through the holes created by the screws. Therefore, it would be beneficial to provide a system and method that allows façade panels to be supported directly by the framing of the building, and/or that does not unnecessarily expose the interior of the barrier panel to additional moisture.
Referring to Exhibits B, C and D of U.S. provisional patent application No. 61/509,109, other single pass systems are shown. The system of Exhibit B is similar to that of the '181 patent, with the façade panels supported directly to the barrier panels. The system of Exhibit C shows a clip that extends out from the barrier panels to provide horizontal support to a façade such as a brick wall. The façade of Exhibit C is supported vertically by its own structure, not by the clip or the framing of the building. The system of Exhibit D includes a zee girt attached through the barrier panels and into the stud of the building. The zee girt provides support for panels to be attached vertically. Nevertheless, the zee girt does not allow for panels to be attached horizontally as they would be to a traditional stud wall. Moreover, the zee girt system requires shims to result in proper panel alignment. Therefore, it would be beneficial to provide a system and method that allows façade panels to be supported vertically directly by the framing of the building in a horizontal manner, and/or that does not unnecessarily expose the interior of the barrier panel to additional moisture.